Drill



Dec, 25, 1923. 1,478,451

1 F. MULLIN DRILL Filed Feb. 14 1919 INVENTOB. Eran/r Mu/fln Patented fies. 25, 123.

FRANK MULLIN, OF ELYRIA, OHIO, ASSIGNOR TO THE WILLYS-OVERLAND COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO.

DRILL.

Application filed February 14, 1919. Serial No. 276,967.

T all whom it may concern Be it known that I, FRANK MULLIN, residin at Elyria, county of Lorain, and State of 0 i0, have invented certain new and useful Improvements in Drills, of which I declare the following to be a full, clear, and

exact description. A

This invention relates to drills, and more particularly to drills adapted for the pur- 10 pose of boring metal articles.

One object of the invention is to provide a device of this character, wherein the cutting elements are capable of radial adjustment with respect to the drill.

A. further object of the invention is to provide a device of this character having means for firmly clamping the cutting elements in a plurality of adjusted positions with respect to the drill.

A further object of the invention is to provide a device of this character, having means for securing a relatively fine adjustment of the cutters, and for varying this adjustment from time to time as occasion may require.

A further object of the invention is to provide a device of this character which is of simple construction and efiicient in opera-- tion.

Further objects of the invention relate to economies of manufacture and details of construction, as will hereinafter appear from the detailed description to follow.

The objects of the invention are accomplished in one instance by the devices and means described in the following specification, but it is evident that the same may be varied widel without departing from the scope of the invention as pointed out in the appended claims.

A structure constituting one embodiment of the invention, which may be the preferred, is illustrated in the accompanying drawing forming a part hereof, in which:

.Figure I is a side elevational view of the improved drill, illustrating the relative position of the operating parts.

Figure II is a view, partially in longitudinal section of the improved drill showing the relative position of the operating parts,

andthe means for clamping the cutting elements in position.

Figure III is an end view of the drill, illustrating the relative position of the cutting elements with respect to the head portion of the drill.

ing the relative position of the various parts of the mechanism.

Referring to the drawings, similar reference characters designate corresponding parts throughout the several views, and the sectional views are taken looking in the direction of the small arrows at the ends of the section lines.

In the embodiment of the invention illustrated herewith, 10 indicates the main body portion of the drill which is provided with a shank 11, adapted to be carried by a head (not shown). A bearing shoulder 12 is provided at the point where the spindle portion joins the main body portion'of the drill, and the body portion is provided with one or more spirally fluted clearing grooves 13, which extend spirally of the longitudinal axis of the drill and are formed in the exterior surface of the body portion, one of these fgrooves preferably bein' associated with each cutting element. paced from the spiral fluted clearing grooves and formed in the body portion of the drill are one or more spirally extending oil grooves'14,'each of these grooves being preferably spaced an equal distance from the two adjacent spiral clearing grooves 13, when two or more of the clearing grooves are employed. The spirally extending clearing grooves 13 serve to provide a means for conducting the material which is cut away by the cutting elements outwardly and away from the material to be operated upon, while the oil grooves 1% serve to provide means for conducting a lubricat ing oil to the cutting elements, for the pur pose of properly lubricating the cutting faces thereof while they are cutting the material. I

- The head portion 15 of the drill is provided with one or more radial grooves 16 extending from the central portion of the drill to the circumference thereof, the grooves preferably being diametrically arranged with respect to each other. A cutting element 17 provided with a cutting edge 18 is slidab'ly positioned within each of the 9, ments in-,po sition.

grooves 16in such a manner that the cutting edge thereof extends outwardly toward the outer surface of the drill where it is adapted to contact with the material which isto be operated uponf-Ea'ch of the cutting elements 17 is provided with a bevel'e'dportion 19 upon the end opposite the cutting edge 18, for a purpose which will presently be described. 7 a

A central opening 20 is provided in the end portion of the drill, the outer extremity of which is smooth, whilethe innerextrem ity 21 isprovided with an interior thread i V as,

for, the-purpose of engaging with a thread -forrned upon the reduced portion 22 of abolt 23. The central portion ofthe bolt 23 is of such size as to beadapted to fit snugly within-the enlarged smooth portion of the opening 20, whileone end thereof is reduced and is provided with an exterior thread so as to be capable of being adjustably positioned withinthe threaded portion 21 of the opening. Adjacent the central enlarged portion 23 of the bolt, and positioned upon the opposite ide thereof from the reduced portion 22 is a shoulder portion 2a, which is beyeled and is adapted to contact with the beveled ends 19 of the cutting elements 17 Extending from the shoulder portion 24 of the bolt is a reduced end portion 25, which is provided with'external threads thereon so as to receive a locking nut 26 and hold the same in position. A clamping washer 27 is preferably interposed between the cutting elements 17 and the lockingnut 26 which is adapted to be firmly clamped between the locking nut and the cutting element when the nut is threaded upon the bolt 3 suflicient distance to properly hold the cutting eleone of the cutters engages with the material which is to be operated upon, whereby they are most advantageously positioned for the purpose of removing that portion of the material which is cutaway; V

In the modified form of the invention illustrated in Figures V and VI, a single cutting element 29 is employed, while a block 32 isfirmly secured in the opposite groove 16 a by means of a screw 30 and pin 31, which serve to firmly position the block and securely hold the same within thegroove, thus providinga means for supporting the adjusting bolt-23 in proper position. The bolt 23 em ployed in this modifieationis similar in all respects to that previously described and the inner edge 33 of the block 32 is squared so that the face thereof, which is presented to the shoulder portion 24% of the bolt 23, is parallel to'the longitudinal axis of the bolt and contacts withthe extreme outer edge of the shoulder, thereby serving as asupport for centering the bolt and maintaining the same in proper position for securing the necessary radial adjustment of the cutting element 29 as the bolt 23 is adjusted within the opening 20 formed in the end of the drill. It will be noticed upon reference to Figure V that as only one cutting element is employed, it is found necessary to use only one of the spirally fluted grooves 35 formed in the outer face of the drill but two oil grooves 36 are provided, each of which is spaced 120 from the cutting edge of the cutting element.

In the operation of this device the shank 11 is inserted in a drilling machine spindle (not shown), by which the drill is supported in the usual manner. The bolt 23 is adapted to be adjustably positioned within the opening 20 by means of the reduced threaded portion 22 being properly threaded within the threaded extension 21 of the opening 20. The bolt 23 is inserted a sufficient distance so that the shouldered portion 2 1 bearing against the beveled end 19 of the cutting element forces the cutting element radially outward a sufficient distance to properly operate upon the material to be cut. The

bolt 23 thus havingbeen properly posi r tioned in such a manner as to correctly adjust the cutting element, the locking washer 27 is placed in position upon the bolt with the inner face thereof bearing against the outer portion of the cuttingelements and the lock nut 26 is then threaded upon-the outer end of the bolt 23, which when firmly threaded against the outer surface of the washer 27 clamps the same securely against the cutting elements, and thereby firmly secures the cutting elements in proper position. If at any time it is desired to change the ad'-' justment of the cutting elements, such change can be accomplished by releasing the lock nut 26, whereupon the bolt 23 may be adjusted within the opening formed in the end of the drill and again clamped in position by tightening the lock nut 26.

The manner of adjusting the cutter 29 in the modification shown in'Figures V and V1, is similar to that employed in the modification illustrated in: Figure I to IV inelusive. opposite portion of the beveled shoulder 24: from that which engages with the cutting element 29 is adapted to bear at all' times against the inner edge of the block32, so as to properly retain the bolt 23 in its central position in the same manner asit would be In this modification, however, the

ments were employed.

er aces While I have shown and described in considerable detail a specific embodiment of my invention, it is to be understood that this showing and description is illustrative only, and for the purpose of rendering my invention more clear, and that I do not regard the invention as limited to the details of construction illustrated or described, nor any of them, except in so far as I have included such limitations within the terms of the following claims, in which it is my intention to claim all novelty inherent in my invention broadly as well as specifically.

What I claim as new and desire to secure by Letters Patent is 2- 1. A drill provided with a central opening therein threaded throughout a portion of its extent, cutters carried by the drill, a threaded member positioned within the internally threaded opening and provided with a beveled portion adapted to contact with the cutters and limit the radial movement of the same relative to the drill, a washer bearing against one side of the cutters, and common means acting through said washer for holding the cutters against removal and looking the threaded member against movement.

2. In a drill having an internally threaded opening formed in one end thereof, radially positioned cutters having their inner ends located adjacent the central opening, a member threaded within the internally threaded opening in the drill and provided with a beveled portion adapted to engage the inner ends of the cutters and limit the inward movement of the same, a washer carried by the said member and bearing against the cutters, and a nut threaded upon the said member and. adapted to bear against the said washer to hold the cutters against movement and at the same time lock the threaded member in adjusted position.

3. A drill bar having a groove cut across the end thereof, a cutter slidable in said groove, said bar having an axial bore intersecting said groove, a bolt threadedly engaging the said bore inwardly of the groove, and provided with a conical portion bearing against the inner end of the cutter, a washer surrounding said bolt and bearing against the said cutter and a nut threaded upon the outer end of said bolt and adapted to bear against the washer to force the latter into locking engagement with the cutter.

4. In a drill bar having a groove out across the end thereof, a cutter slidable in said groove, said bar having an axial bore intersecting said groove, said bore being smooth for a portion of its length inward of the groove, and the inner end of the bore being constricted and threaded, a bolt hav-' ing a smooth'portion for fitting within the smooth portion of the bore and an inner constricted. end threaded into the threaded portion of the bore, said bolt near its outer end having a conical portion adapted to bear against the inner end of the cutter and means on the bolt for locking the cutter in adjusted position and the bolt against movement.

In testimony whereof, I afiix my signature.

FRANK MULLIN. 

